Question 31Steam Plants - QMED

The correct answer is D) 12. The mechanism for operating the register air doors is represented by item 12 in the illustrated air register and burner assembly (Illustration SG-0016). This is the air register damper, which controls the amount of air flowing through the register and into the space being heated. The other answer choices are incorrect because they represent different components of the assembly, such as the air register (2), the primary air inlet (4), and the burner assembly (6), but do not specifically depict the mechanism for operating the air register doors.